Amazon.com Inc. marked its first day as owner of upscale grocer Whole Foods Market Inc. by cutting prices on a number of organic goods at locations across Canada and the United States, a first salvo in a battle observers believe could alter the grocery industry’s competitive landscape.

Organic avocados were selling for $1.99 each at Whole Foods’ Yorkville location in Toronto on Monday, a 76-cent price-cut. Lean pasture-raised ground beef had been reduced to $5.99 per pound, from $8.57. And the price of responsibly farmed Atlantic salmon had been slashed to $5.99 per 170 grams from $7.99.

The price tags of those products and some others sported the logos of Austin, Texas-based Whole Foods and Seattle, Wash.- based Amazon, which announced their coupling in June. A sign near the end of one checkout line boasted the two companies are “growing something good.”

“Generally speaking, I think it was a very, very good day for both Amazon and Whole Foods,” said Sylvain Charlebois, a professor who researches food distribution and policy at Dalhousie University in Halifax. “It is clearly sending a statement to the entire food market in North America.”

There are only 13 Whole Foods stores in Canada, mostly in and around Toronto and Vancouver, in addition to more than 400 locations in the U.S.

But Amazon’s US$13.7 billion acquisition of the upscale supermarket chain, a transaction that closed on Monday, has jolted competitors.

Morgan Stanley said Sunday in a research note that they believe lower Whole Foods (WFM) prices could increase the company’s market share, as their most recent AlphaWise survey found approximately seven out of 10 people who don’t shop at the chain said price was the chief obstacle.

“We see lower pricing leading to accelerating WFM share gains,” wrote the analysts. “In essence, we believe WFM prices are 5 per cent higher than competitors (excluding Proteins) and think (Amazon) has the ability to close that gap.”

In Canada, Amazon’s entry into the market comes at a time of already heightened competition.

Grocers in Alberta and Ontario are facing minimum wage hikes over the coming years, which companies have said will increase their costs substantially.

Charlebois, who noted that Whole Foods’ prices were already “slightly inflated” and that the move was likely as much intended to lure back customers who had left the chain, said competitors such as Wal-Mart could react by adjusting their pricing strategies.

Some grocery stocks have fallen off since Amazon announced it was buying Whole Foods, which will continue to operate under the same brand, a press release said last week. Shares of U.S.-based Kroger Co. closed at $21.72 on Monday, down 2.5 per cent from June 16, when Amazon’s acquisition was announced.

In Canada, Metro Inc.’s stock price was $43.16 on June 16, and finished Monday at $41.34, a 4.2 per cent decline. Shares of Loblaw Companies Ltd. were $72.79 when the Whole Foods deal was announced, and closed at $67.26 on Monday, a 7.6 per cent drop.

According to a release from Whole Foods and Amazon, the lower prices are just a “down payment” on a plan to make their organic offerings affordable for all. Amazon Prime — a membership program offering free two-day shipping and the streaming of movies and TV shows — will eventually become Whole Foods’ customer rewards program, “providing Prime members with special savings and other in-store benefits,” the release said.